A) 86
B) 90
C) Both (A) and (B)
D) None of these
Correct Answer: D
Solution :
Let a be the first term and d be the common difference of the A.P. We have, \[{{a}_{3}}+{{a}_{7}}=6\] and \[{{a}_{3}}{{a}_{7}}=8\] \[\Rightarrow \]\[(a+2d)+(a+6d)=6\]and \[(a+2d)(a+6d)=8\] \[\Rightarrow \]\[2a+8d=6\] and \[(a+2d)(a+6d)=8\] \[\Rightarrow \]\[d=\pm \frac{1}{2}\] Case-I: When \[d=\frac{1}{2};\text{ }a=1\] Case-II: When \[d=-\frac{1}{2};\,a=5\,\Rightarrow \,{{S}_{16}}=20\]
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